This invention relates generally to apparatus for jogging sheet material articles which are deposited in a hopper. It relates particularly to a jogging apparatus which is suitable for use in high speed signature handling systems in which signatures are automatically fed into the top end of a hopper while signatures are being withdrawn from the bottom end thereof.
In many known types of high speed signature handling systems signatures are automatically fed into the top end of a hopper while signatures are being withdrawn from the bottom end thereof. Such type of systems may be found in disclosures such as U.S. Pat. Nos. 3,674,258 and 3,690,650 and 3,825,246. As explained in U.S. Pat. No. 3,690,650, it is often desirable to jog the signatures as they descend in the hopper, in order to assist their descent, and to help to correctly position the signatures within the hopper. U.S. Pat. No. 3,690,650 discloses two types of apparatus for jogging signatures as they are fed into a hopper.
Other known systems for jogging sheet material articles can be found in disclosures such as U.S. Pat. Nos. 3,593,992, 2,393,254, 1,851,972, 1,949,764, 1,235,477 and 702,966. According to the disclosures of most of these patents, jogging takes place against sheet material articles which are essentially at rest within the hopper and by means of fairly complicated structures having numerous moving parts.